Malicious software (or malware), often generically called viruses, is computer software which deliberately does something harmful to your computer. Once downloaded, malware can be passed from one computer to another. Malware is usually downloaded to a computer by hiding inside rogue (and sometimes legitimate) software packages: the Trojan horse (or Trojan).
If a Windows or Mac OS X operating system gets infected by malware, it could cause the loss of important files; business files, digital music and movies, and pictures could be wiped out by a single infection. The malware may slow down the computer or become annoying by sending email to all of the infected users contacts. Worse, it may delete or copy sensitive information on the infected computer or mobile device.
Infectious Mobile Devices
Android devices and some versions of the Apple iOS mobile operating system are vulnerable to malicious code contained in PDF files. Security researchers at Intego noted that while there is currently no known malware for iOS, files that flow through mobile devices and into home and office computers by email or remote storage can contain malware and worms that are harmful to the Mac and Windows operating systems. For example, once infected, an iPhone would act as an asymptomatic carrier, allowing cybercriminals to access confidential information, intercept phone conversations or take over other aspects of the infected device.
While Mac malware is scarcer than Windows malware, over the last ten years threats targeting Mac OS X have been on the rise and have become more sophisticated. In addition, Macs can pass on files that contain malware to Windows users. For this reason, a layered approach to security is the best defense, including the use of a firewall and Mac antivirus that detects and stops Windows viruses as well as Mac malware.
In addition to the Linux Virus, Macro Virus, Windows Virus, and Mac Virus, a number of other types of malware exist for computer operating systems. This includes spyware, adware, keyloggers, and scareware (rogue software that claims to serve a purpose, usually pretending to be security software).
- malware. Dictionary.com. http://dictionary.reference.com/browse/malware, (accessed: July 13, 2011).
- Definition: Trojan horse, searchsecurity.techtarget.com, (Accessed July 13, 2011).
- Apple Macintoshes Targeted by Porn-Based Computer Virus, FOXNews.com, November 02, 2007.
- The Mac Security Blog. Do You Need an Antivirus for Your Mac? Definitely, Yes., blog.intego.com, December 4, 2008.
- Amy Gahran. iPhone, iPad users: Watch out for malicious PDF files, CNN, July 11, 2011.
- The Mac Security Blog. iOS PDF Vulnerability Creates Security Risks, Allows Easy Jailbreaks, blog.intego.com, July 7, 2011.
- Killian Bell. Intego’s VirusBarrier for iOS Will Stop Your iPhone From Being A Typhoid Mary, Cult of Mac, July 12, 2011.
- 10 Years of Mac Malware: How OS X Threats Have Evolved (Infographic)